1. Field of the Invention
The present invention relates to a tool, and more particularly to a tool having a rotatable driving head.
2. Description of the Prior Art
A typical wrench is disclosed in U.S. Pat. No. 4,901,608 to Shieh and comprise a driving head rotatably secured to a handle. The handle includes a gear and a pinion of different sizes slidably engaged in the handle for selectively engaging with the teeth of the driving head and for controlling the rotational movement of the driving head. However, the gear and the pinion may not be completely engaged with and completely disengaged from the teeth of the driving head such that the rotational movement of the driving head may not be easily operated. In addition, a number of parts and elements are required and may not be easily assembled.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the conventional wrenches.